Current generator cell



for use in electrolytic devices of this character.

United States Patent 3,093,513 CURRENT GENERATOR CELL John McCallum,Worthington, Ohio, Theodore B. Johnson, Stratford, Conn and Walter E.Ditrnars, Jr.,'and Leslie 1). McGraw, Columbus, Ohio, assignors, bydirect and mesne assignments, to Remington Arms Company, Ina,Bridgeport, Conn., a corporation of Delawere No Drawing. Originalappiication Jan. 3, 1958, Ser. No. 706,890, now Patent No. 2,979,553,dated Apr. 11, 1961. Divided and this application Nov. 14, 1960, Ser.No. 68,582

5 Claims. (Cl. 136-100) This invention relates to current generatingcells, particularly to primary cells having negative electrodes (anodes)comprising titanium alloys in conjunction with alkaline electrolyteshaving the properties of avoiding formation on the surface of thenegative electrode (anode) of a highly resistant or current-blockingfilm or coating. The present application is a divisional application ofour application Serial No. 706,890, filed January 3, 1958, now US.Patent 2,979,553, which was a continuation-in-part of applicationsSerial No. 349,098, filed April 15, 1953; Serial No. 405,252, filedJanuary 20, 1954; Serial No. 405,494, filed January 21, 1954; and SerialNo. 466,582, filed November 3, 1954. All four of the last-mentionedapplications are now abandoned.

It is well known that certain metals including aluminum, magnesium, andtitanium in contact with many electrolytes acquire a surface film thateffectively blocks the flow of electrons. Advantage has long been takenof this property of such metals in the construction of such electrolyticapparatus as rectifiers, capacitors, and lightning arrestors. Titanium,by reason of its filrn-forming properties, has frequently been mentionedas a metal suitable Because of such film-forming properties, titaniumhas not been seriously considered as a possible useful material for thenegative electrode (anode) of a primary cell.

On the other hand, it is Well known that certain electrolytes severelyattack titanium metal. Hydrofluoric acid, for example, is commonly usedto clean titanium products, and hydrogen gas is vigorously evolvedthereby. Red fuming nitric acid can attack titanium metal with explosiveviolence. Prior to this invention, then, titanium was regarded as eithertoo passive because of current blocking films in many electrolytes, ortoo active because of spontaneous corrosion by other electrolytes.Either situation rendered titanium substantially useless as a negativeelectrode (anode) for a primary cell.

It has been discovered as a part of the present invention that certainalloying elements added to titanium make titanium alloys that areelectrochemically active, but at the same time prevent chemical activityand spontaneous corrosion. When the alloys are used as primary cellanodes (negative electrodes) both the titanium and the alloying elementsare consumed in the delivery of useful energy.

By varying the type and amount of alloying elements added to titanium,in accordance with the present invention, the chemical andelectrochemical properties of titanium can be controlled to providenovel primary cell anodes (negative electrodes) with a variety ofdesirable properties, depending on the desiredend use.

This invention includes the discovery that concentrated alkalineelectrolytes have the property of inhibiting or greatly retardingtheformation of nonconductive or rectifying films on the surfaces ofvarious titanium alloys and instead maintain the surfaces substantiallyfree from any currentblocking film, and permit the use of lightweightdurableititanium alloys as primary cell negative electrodes (anodes).

Certain preferred electrolytes provide best results for variouspurposes. Propercombinations of negative electrodes (anodes),electrolytes, and positive electrodes (cathodes), in accordance withthis invention, provide novel primary cells that may be custom designedto have combinations of characteristics not obtained in prior cells. Forexample, such cells can be made to have long shelf life and low drain,or to provide high currents at high voltage, or to have small size andlight weight. Combinations of these properties in various degrees canalso be obtained.

The cathodes or depolarizers (positive electrodes) used in cells of thepresent invention may be those well known in the art, such as mercuricoxide, lead dioxide, manganesedioxide, nickel oxides. The depolarizers(positive electrodes) may or may not be formed on special supports suchas the titanium supports of US. Patent 2,631,- of Fox. The support forthe depolarizer (positive electrode) is another part of the cell, andhas no material bearing on the function of the anode (negativeelectrode). The Fox patent asserts that titanium, used as a supportingstructure for the depolarizer (the positive electrode in a currentgenerating cell), improves the depolarizer voltage and operatingcharacteristics Without taking part in the electrochemical reaction. Thetitanium alloy anodes (negative electrodes) of the present inventionhave nothing to do with the behavior of the cell depolarizers orcathodes (positive electrodes), and the alloy anodes areelectrochemically consumed as an integral part of'cell discharge. Thesefacts are mentioned here to avoid any confusion between these twoessentially different uses of titanium.

Primary cell anodes according to the present invention comprisetitanium-rich alloys containing at least 50 atomic percent titanium. Theaddition of alloying materials such as molybdenum, vanadium, chromium,cobalt, nickel, niobium, tantalum, and tungsten, from periodic groups V,VI, and VIII decreases the spontaneous corrosion of the anode andthereby increases the shelf life of the cell. Such alloying elements canbe called titanium passivating elements. Alloying additions of materialssuch as aluminum, beryllium, and boron, from periodic groups II and LII,increase the voltage and current capacity of the cell. Such alloyingelements can be called voltageimproving and current-improving elements.Various combinations of these and other materials may be used intitanium alloys to obtain desired properties, as described herein. Theanodes of this invention are free from any substantial current blockingfilm and are in direct contact with theelectrolytes. The alloys areconsumed in the discharge of cells by the flow of ions from the anodesto the electrolytes.

The present invention contemplates the use of alloys of titanium as theactive anode materials that directly furnish electrical energy inprimary cells. It has been discovered that many of these titanium alloysexhibit unique properties as primary cell anodes. In particular, certainalloy additions to titanium decrease spontaneous corrosion, therebyimproving shelf life. Alloying additions can also increase the closedcircuit voltage of titanium containing cells, increase the availablecurrent density, or reduce the weight and size of the anode. Variouscombinations of these advantages may also be obtained by controlling thetitanium alloy composition.

The titanium alloy anodes may be made in the form of shaped solidalloys, rolled foils, sintered powders, or compressed powders, bymethods well known in the primary cell art. It isimportant to avoidgross heterogeneity of the alloy, asnonuniformity may result in localgalvanic action, which destroys shelf life of the cell. The electrolytemust contact the'titanium alloy anode but it may be either liquid orgelled in accordance with common practices in the primary cell art. Thecathode depolarizer may also be made in conventional forms and shapes.

ANODE MATERIALS We have discovered that titanium alloys with variouselements of groups V, VI, and VIII of the periodic table used as primarycell anodes have low enough spontaneous corrosion to provide long shelflife for the cells containing them as anodes. In this group of alloys,increasing the concentration of the alloying addition results inincreasing the chemical passivity of the anode. However, when thealloying addition is present in a certain minimum desired amount,further additions do not appreciably afi'ect the chemical passivity orcorrosion resistance. For example, in a titanium molybdenum alloy, thecorrosion resistance of the alloy in primary cell electrolytes graduallyincreases with increase in molybdenum concentration until the molybdenumconcentration is about 25 to 29 weight percent. Further increases ofmolybdenum do not materially increase the corrosion resistance.

To illustrate this discovery, corrosion rates were measured by hydrogenevolution in saturated potassium hydroxide solutions containing a smallamount of solubilized potassium tartrate. Results are shown in Table Ibelow, together with anodic closed circuit voltages at an anode currentdensity of 5.0 milliamperes per square inch. The closed circuit voltagesare measured against a saturated calomel electrode (SCE) for purposes ofexperimentation. In primary cells containing this electrolyte,conventional cathodes such as mercuric oxide, nickel oxides, and manganese oxides may be used.

e Saturated ealomel electrode.

We have discovered further that this chemical passivation effect can beobtained by alloying titanium metal with other transition metals fromperiodic groups V, VI, and VIII. A certain minimum concentration ofalloy additions appears to be desirable for the minimum of chemiicalactivity plus maximum of electrochemical activity as a primary cellanode. It appears that there are electronic interactions between atomsof the alloys and When the total number of valence electrons is aboutfive for each titanium atom, we have a preferred alloy for a primarycell anode. In this instance, valence electrons means the total numberof electrons in the transition metal outside of the preceding inert gaselectronic core as described in the periodic table. Thus, titanium canbe considered to have 4 valence electrons, vanadium 5, chromium 6, iron8, cobalt 9, nickel 10, and so forth.

To illustrate this discovery, various titanium alloys were givencorrosion tests in primary cell electrolytes, and the following resultswere obtained:

For best cell performance, the minimum amounts by weight of thepassivating elements in titanium alloy anodes should be: 29 percentmolybdenum, 13 percent vanadium, 18 percent chromium, 29 percent cobalt,38 percent nickel, 24 percent niobium, 35 percent tantalum, and 39percent tungsten.

To obtain optimum results in the chemical passivation of titanium byalloying, the alloy should be one phase and homogeneous. Titanium metalhas a hexagonal closepacked crystalline structure below 882 C. Whenalloyed with some of the other transition metals, however, titaniumassumes a body centered cubic crystalline structure in which greatersolid solubility is possible. Titanium forms intermetallic compoundswith some metals. It is important for optimum performance and minimumself-discharge that only one crystalline structure be present for theentire alloy, and that mixed phases, structures, or compounds be absent.To illustrate this point, two Ti--30Mo alloys were prepared, one byquenching the alloy rapidly from melting temperature, the other byslowly annealing from melting temperature to ambient room temperatureover a period of days. Spontaneous corrosion tests were then made, asdescribed earlier, and results were as follows:

Table III Gassing Rate,

Alloy: cc. I-Iz/day-in. Ti-30Mo (quenched) 0.0021 Ti-30Mo (slowannealed) 0.018

The slow annealed sample has a mixture of crystalline structures(hexagonal close packed plus body centered cubic). Each structure has adifferent alloy composition, and corrosion resistance is therebydecreased.

Mixtures of various metals may be alloyed with titanium to decreasechemical activity and increase electrochemical activity. For bestresults, the concentration of valence electrons should be at least aboutfive for each titanium atom and the resulting alloy should be one phaseand homogeneous. The required concentrations for alloying additions areaccurate to within about plus or minus 20 percent of the valuescalculated on this basis. To attain homogeneity, the usual techniques ofmetallurgy such as quenching, remelting, annealing, should be employed.Since titanium atoms and all atoms of the alloying additions participatein the primary cell anode reaction, it is possible to devise a varietyof anodes with a variety of electrochemical properties.

Titanium alloys passivated according to the principles of this inventionhave exceptional stability as primary cell electrodes at elevatedtemperatures. To illustrate this discovery various primary cell anodeswere placed in 14 molar potassium hydroxide and corrosion rates weremeasured by hydrogen evolution. Results were as follows:

Table IV At ;l:20 F. At lfi5=lz5 F.

Anode Gassing Open Gassing Open rate, circuit rate, circuit cc. Halvoltage cc. Hz/ voltage day-in. vs. SCE day-in. vs. SCE

Amalgamated zinc 0.17 1.66 29 l. 73 Titanium O, 31 l. 55 93 -1. 63Titanium, 30 weight percent molybdenum 0.005 1.05 1. 2 1.40 Titanium,14.9 weight percent vanadium. 0. 3 1. 28 0. 45 l. 48 Titanium, 40 weightpercent vanadium 0. 045 1. 22 1.8 l. 46 Titanium, 35 weight percentmolybdenum, 5 weight percent aluminum 0. 005 l. 15 0. 42 1. 40

These data show that for a titanium alloy anode containing 14.9 percentvanadium, the gassing rate increases by only one-half when thetemperature is increased from 80 F. to F.; while, in contrast, thegassing rate for an amalgamated zinc anode (commonly used in commercialprimary cells) increases 170 times, and the gassing rate for anunalloyed titanium anode increases 300 times, for the same temperatureincrease. Furthermore, the gassing rates at 165 F. for the othertitanium alloy anodes listed above are less than one-tenth of thegassing rate for an amalgamated zinc anode, and less than onefiftieth ofthe gassing rate for an unalloyed titanium anode at the sametemperature. In addition, the voltages for the titanium alloys increaseby at least two-tenths volt compared to a voltage increase of less thanone-tenth volt for amalgamated zinc or titanium anodes.

The solid products formed on the surface of some titanium alloy anodesduring discharge of cells are not current-blocking films as might beencountered on pure and unalloyed titanium anodes in the sameelectrolyte. For example, pure titanium anodes in primary cells havingsaturated KOH electrolytes and mercuric oxide cathodes polarize after ashort drainage because of the buildup of current-blocking films. Ti30Moalloy anodes in the same cells deliver energy at practically constantvoltage until the alloys are completely consumed by the primary cellreactions.

Sintered titanium alloy anodes provide higher currents and higherclosed-circuit voltages than rolled anodes of equal weight, because thesintered anodes have greatersurface area per unit weight. In addition,high open-circuit voltages are obtained, without additional anodepretreatment, upon immersion of the sintered anodes in the cellelectrolytes. The high voltages indicate active surfaces, Which makesintered anodes still more advantageous over rolled metal anodes, manyof which must be cleaned and given an activation treatment beforeimmersion in the cell. For example, a sintered Ti27Mo-10Al anode had aninitial open-circuit voltage of 1.540 volts vs. SCE in 14 M KOHelectrolyte, while a solid Ti27MO-10 Al anode had an initialopen-circuit voltage of 1.298 volts in anotherwise identical cell.

A cell having a Ti27Mo--10Nb anode made and tested in connection withthis invention illustrates, typical results obtainable with small cellsusing titanium alloy anodes. The cell was enclosed in a small cylinder0.54 inch in diameter and 0.34 inch high. The anode comprised a discabout 0.455 inch in diameter and 0.01 inch thick, weighing 0.15 gram.The disk had been cold rolled to the desired thickness, stamped to shapeand anodically etched in a saturated aqueous solution of potassiumhydroxide containing 0.25 M of potassium tartrate.

The cell electrolyte was 0.5 cubic centimeter of a solution of 55 weightpercent (14 M) potassium hydroxide in distilled water.

The cathode was made of 1.33 grams of compacted powder comprising 92weight percent red mercuric oxide and 8 weight percent graphite.

The cell reached an equilibrium closed circuit voltage of 0.88 voltinstantaneously on a load ofabout 10,000 ohms and maintained thisvoltage within 11 percent throughout 90 days of continuous drain at atemperature of 70:2" F. An additional 70 days of continuous drain wasobtained before the cell voltage fell to 0.81 volt.

This cell illustrates the advantage of an extremely constantclosed-circuit voltage at constant temperature. The constancy ofclosed-circuit voltage is useful in a primary cell to provide areference voltage while on drain. Such a cell is useful for controlinstruments, electric clocks, transistor circuits, etc. a

This cell also has the advantage that it can be discharged at 32 F. atabout 0.4 volt until all the active materials are consumed; whilecommercial cells employing amalgamated zinc anodes and mercuric oxidecathodes yield only a small fracti n of their designed ampere-h urcapacity at 32 F. Furthermore, since the titanium alloy anode,electrolyte, and cathode of this cell are completely stable and do notgas appreciably, a cell of this-type has exceptionally long shelf lifeand does not leak on stor- Table V Closed circuit voltage vs. SCE at 5.0

Ina/in.

Closed circuit voltage of coils with commer cial HgO electrodes, voltsPolarizing current density, maJin.

Anode Both the titanium and the alloying addition, aluminum, beryllium,or boron, are consumed during the cell reaction. This leads to extremelylow equivalent weight. Therefore, small, light-weight, high capacityprimary cells may be made with anodes of these materials. Above certainmaximum concentrations of alloying additions, however, these alloysexhibit increased spontaneous corrosion, and, therefore, decreased shelflife of the primary cells using them. When the alloying addition ispresent in the anode in an amount below a certain weight percentage, the:cell provides increased potential at high anode current density Withouthaving significantly reduced shelf life. For example, the shelf life isbest for beryllium contents less than 9 weight percent, aluminumcontents less than 25 weight percent, and boron contents less than 10weight percent. Anodes containing higher concentrations of theseflloying materials provide still higher currents at high closed circuitvoltages. Such highly concentrated alloys give the higher currents andvoltages with greater efi'iciency than the alloying elements alone andprovide unusually high wattage per unit of weight or volume. Cells usingsuch anodes are useful for various purposes requiring high drains forshort periods, despite their shorter shelf lives.

Another part of our discovery is that ternary and quaternary alloys oftitanium can provide unique anode materials for primary cell anodes. Forexample, the addition of aluminum to a chemically passivatedtitanium-molybdenum alloy increases both the closed circuit voltage andthe maximum anode current density. This advantage is illustrated bydrainage experiments in saturated potassium hydroxide electrolyte.

Table VI Closed circuit voltage at 5.0 rna/in. vs. SCE

Polarising current density maJin.

Anode (numbers re- Ti-30 M0 Tl-35 M0-5 Al.

Other ternary additions to a binary alloy of titanium with a group V,VI, or VIII metal improve drainage properties when the ternary alloy isused as a primary cell anode. For example, 10 weight percent niobium or10 weight percent vanadium added to a titanium30 weight percentmolybdenum alloy anode allows longer continuous drains at a moreconstant closed circuit'voltage and at larger anode current densities.Similar improvements with ternary additions of other elements in theperiodic table. to binary alloys of titanium with an element of group V,VI, or VIII are obtained where the two main principles of this inventionare followed: (1)

The total concentration of valence electrons should be at least aboutfive for each titanium atom in the alloy, and (2) all elements should bein solid solution in one another, one phase, and homogeneous, inaccordance with the well-known principles of metallurgy. For anontransition element, the number of valence electrons is equal to thenumber of the periodic group in which the element appears.

ELECTROLYTES! The preferred electrolytes for primary cells containingtitanium alloy anodes are concentrated alkalies. They may be in the formof liquids, gelled liquids, or pastes. Liquid electrolytes are preferredfor those cells requiring high drainage rates. Gelled liquids or pastesare preferred for cells designed for low drainage rates. Gelling agentssuch as starch or glutens or others well known in the primary cell artcan be used.

Generally, the more concentrated the cell electrolyte, the greater isthe watt-minute capacity of the cell for a given size. Thus, saturatedsolutions or saturated solutions having also a minor amount of solidphase are desirable. The hydroxide concentration should be at leastabout moles per liter, preferably at least about 11 moles per liter.

The cathode or depolarizer is preferably an oxygen yielding compound,such as mercuric oxide, the oxide or peroxide of silver, cupric orcuprous oxide, lead peroxide, potassium permanganate or another alkalinepermangana-te, as is well known in the primary cell art.

A significant advantage of this invention is that where a suitabecombination of cathode and electrolyte is chosen for stability, highdrain, small size, light weight, or some combination of theseproperties, then a titanium alloy anode can be constructed for thecathode-electrolyte combination that enhances these properties evenfurther. For example, we have found Ti30Mo anodes in conjunction withalkaline electrolytes and mercuric 0X- ide cathodes to be more stable,and thus to provide longer shelf life for the cells, than any otherknown anode with same cathode-electrolyte combination. For best resultsthe titanium alloy should be constructed with elements such that one ormore of the reaction products is soluble in the chosen electrolyte, andthe amounts of alloying additions to titanium should be such that thetotal concentration of valence electrons is at least about five or eachtitanium atom and the alloy anode is one phase.

The electrolytes are preferably made with potassium hydroxide oralkaline potassium salts. Most titanium alloys provide slightly higheropen circuit voltage with saturated sodium hydroxide electrolytes thanwith saturated potassium hydroxide electrolytes. However, the titaniumalloy anodes can be drained at larger current densities with thealkaline potassium electrolytes, and for most applications this makesthe alkaline potassium electrolytes generally more desirable.

The concentration of a potassium hydroxide electrolyte affects thevoltage characteristics, especially at high current densities. In therange from 11 molar to saturation, increasing concentration of the KOHincreases the voltage at a given current density and provides usefuloutput at higher current densities.

Zincate, tartrate, and aluminate additions to KOH of 11 M and higherconcentrations increase the voltage at a given current density andprovide useful output at higher current densities.

Typical experiments illustrating the characteristics of various titaniumalloy anode primary cells are shown in the data of Table VII. Date fortitanium metal anodes are included for comparison. The anode voltageswere measured in reference to a saturated calomel electrode. For actualcell operation, various well-known cathodes, such as mercuric oxide,nickel oxide, or carbon-air electrode were used. The cell potentials inthese cases may be readily calculated by known methods.

The extended drainages indicated in Table VII were taken at timesvarying from two hours to four weeks.

In Table VII, column 5 indicates whether current at the density shownmay be drawn for several hours from the primary cells at constantpotential. Column 6 is a critical current density at which the voltageof the primary cell abruptly decreases. Column 7 denotes shelf life asmeasured by corrosion of the anode, the shelf life being inverselyproportional to the gassing rate.

Table VII.--Pr0perties of Primary Cells Comprising An des of Titaniumand its Alloys at Ambient Room Temperatures (25 Q15) A. TITANIUM METALANODES Drainage Shelf life, open circuit Anode Electrolyte Additive Isextended Polarizing gassing rate,

Potential in volts (vs. drainage current cc./(lay/sq. in.

SCE) at ma./sq. in. possible? density,

atma./sq. in. ma./sq.1n.

5.0 M KOH -1.10 at 1.0 No 2 -1.32 at 1 i No 0.4 1.33 at 1.5 No 0. 31 do1.39 at 2.3 No 0.13 (5) Timetal Satd KOH 0.25 M K104114011 (110- 1.34 at5.0, 1.26 at Yes, at 5.0.- 90.0 2.7

tassium tartrate). 10.0, -1.20 at 20.0.

B. ANODES COMPRISING ALLOYS OF TITANIUM WITH METALS OF GROUPS V, VI, ANDVIII (1) Ti 2.0 (Jr Sat'd KOH 0.25 M K2C4H400 -1.11 at 5.0 Yes, at 5.0.-10.0 2.6 (2) Tl-20.0 Or Satd KOH 0.25 M K2C4G400- Po1ar1zedat0.5ma./sq.0. 0008 in. (3) T Mo. Satd KOH 0.25 M KzC4H4Oq.. 1.28 at 5.0 Yes, at5.0-- 40.0 3.5 (4) 'li-5.0 Mo.. Sntd KOH 0.25 M K2C4H4O -1 23 at 5 0 -d040.0 1. 5 (5) Ti-16.0 Mo. Satd KOH 0.25 M K204H400 l 13 at 5 0.-.. 30.00. 24 (6) Ti-20.0 Mo. Sat'd KOII 0.25 M K2C4H40fl 1 07 at 5 0...- 30.00. 031 (7) Ti-30.0 Mo (quenehed). Sat'd KOH 0.25 M K204H408 l.05 at 5.0d0 50.0 0.0044 (8) Ti-30.0 Mo (quenched) Satd KOH None 0.98 at 3.0 Yes,at 3.0.. 6.0 (9) Tl-30.0 Mo (slow annealed). Satd KOIL- 0.25 M KrC HlOn0.007 (10) Ti-50.0 Mo 3 Sat'd K011- 0.25 M K2C|H4Ot 1.01 at 5.0 Yes, at5.0... 90.0 0.0014 (11) Ti-38.0 Ni... Satd KO 0.25 M KZO4H408 Yes, at2.0-.. 10.0 1. 5 (12) Ti-16.0 V Sat'd KOIL- 0.25 M KaClHlOa Yes, at5.0... 30.0 0.65 (13) Ti-40.0 V (queuehed) Satd KOH" 0.25 M K2C4H400..do 400 0.0017 (14) Ti'40.0 V (slow annealed) Satd KOH.. 0.25 MK2C4H4Og O. 0042 (15) Ti-14.9 V (quenched) Satd KOH.- 0.25 M 110411400.- 40. 0 0. 24 (10) 'Ii-14.9 V (slow annealed). atd KOH 0.25 MK1C H 0 30.0 0.70 (17) Ti-40.0 V (quenched)--..- Satd KOH Non 40.0 (18)T1-3.0 V Satd KOH 0.25 3.0

See footnotes at end of table.

Table VII-Continued O. ANODES COMPRISING ALLOYS OF TITANIUM WITH METALSOF GROUPS II AND III Drainage Shelf life, open circuit Anode ElectrolyteAdditive Is extended Polarizing lgassing rate,

Potential in volts (vs. drainage current cc./day/sq. in.

SUE) at Ina/sq. in. Possible: density,

at maJsq. in. ma./sq. in.

(1) Ti3.0 Al Satd KOH 1.40 at 5.0 Yes, at 5.0... 60.0 5.0 (2) T -10.0 Al1.35 at 5.0 d 30.0 26. 6 (3) Ti-33.0 Al -1.68 at 5.0 200. 50.0 (4)Ti-60.0 Al -1.57 at 5.0 700. 0 2, 300. 0 (5) (P -33.0 Al l.73 at 1.0 2.0 (6) T1-33.0 Al 1.6 at 5.0. (7) Ti-33.0 Al 1.67 at 5.0 (8) Ti-33.0 AL.Polarized at (9) T1012 B -1.24 at 5.0 6. 0 (l0) Ti-1.2 B 1.327 at 5 10.0(ll) Tl-13.0 B 1.46 at 5.0 48.0 (12) Ti-13.0 B 1.35 at 6.0 (13) Ti-13.01.38 at 5.0 (14) Ti-LO Bo 1.41 at 5.0 4. 3 (l5) Ti-15.0 Be 1.66 at 5.097. 0 (16) 'li-28.0 Be 1.78 at 5.0 1, 000. 0 (17) Ti-40.0 Be 1.66 at 6.02. 300.0

D. ANODES COMPRISING TERNARY ALLOYS OF TITANIUM (I) Ti-35.0 Mo-5.0 A1Satd KOH 0.25 M K30413140 -1 15 at 5. 0 Yes, at 5.0..- 200. 0 0.0035 (2)Ti-35.0 M0-5.0 Al Satd KOH None 1. at 5 0 do 200. 0

Commereial Rem-0ru 55 sheet titanium.

3 Numbers indicate weight percents of alloyed elements.

5 Not measured, but slight.

7 Not measured, but gassing inhibited.

What is claimed is:

1. A primary cell having an anode consisting essentially of titanium andabout 33 to 60 weight percent aluminum, a cathode, and an electrolytecomprising potassium hydroxide.

2. A primary cell having an alkaline electrolyte and an anode that is analloy consisting essentially of titaniurn and about to weight percentberyllium.

3. A primary cell having an anode consisting essentially of titanium andabout *15 to 40 Weight percent beryllium, a cathode, and an electrolytecomprising potassium hydroxide.

4. A primary cell having an alkaline electrolyte and an anode that is analloy consisting essentially of at least 5 0 atomic percent titaniumwith a voltage-improving and current-improving element present in aneiiective amount I Not measured.

4 Negligible, but not measured. 6 Not measured, but vigorous gassing.

5 Not measured, but gassing rate high.

9 Not measured, but negligible.

References Cited in the file of this patent UNITED STATES PATENTS FoxMar. 10, 1953 Johnson et al June 21, 1960

5. A PRIMARY CELL HAVING AN ALKALINE ELECTROLYTE AND AN ANODE THAT IS ANALLOY CONSISTING ESSENTIALLY OF TITANIUM WITH A VOLTAGE-IMPORVING ANCURRENT-IMPROVING ELEMENT PRESENT IN AN EFFECTIVE AMOUNT AND SELECTEDFROM THE GROUP CONSISTING OF UP TO 60 WEIGHT PERCENT ALUMINUM, UP TO 40WEIGHT PERCENT BERYLLIUM, AND UP TO 13 WEIGHT PERCENT BORON.